Truck hoisting crane



Aug. 13, 1929. E. c. PITCHER TRUCK HOISTING CRANE Filed Deb. 27, 1927 2 Sheets-Sheet w m ww Aug. 13, 1929.

E. c. PITCHER 1,724,411

TRUCK HOISTING CRANE Filed Dec. 27, 1927 2 Sheets-Sheet 2 Fatented Aug. 13, 1929.

ELMER o. IPITCHER, or OAKLAND, CALIFORNIA.

set. I

TRUCK HOISTING CRANE.

Application filed December 27, 1927. Serial No. 242,895.

My invention relates to improvements in a truck hoisting crane, and it consists in the combinations, constructions, and arrangements hereinafter described and claimed.

An object of my invention is to provide a truck hoisting, crane that makes use of the same motive power for propelling the truck and for actuating the crane. The parts are so designed that one operator may control the movements of the truck and also the crane.

A further object of my invention is to provide a device of the type described which makes use of novel means for moving a counter-weight as the crane is moved so that the weight will counter-balance the load car ried by the crane, irrespective of the particu lar position of the crane with respect to the truck body. The moving of the counterweight prevents the crane from rolling the truck body or from over-turning it, and permits a standard truck body to be used. This would be impossible if it were not for the counter-weight and the novel means. employed for moving it.

A further object of my invention is to provide a device of the type described which makes use of a common shaft having reels or drums mounted thereon, and cables connecting the drums with the crane and the counter-weight, so that a movement of the drum will swing the crane and move the counter-weight at the same time. way the load supported by the crane is counter-balanced.

A further object of my invention is to provide a device of the type described which can be built on a standard truck and which utilizes the engine of the truck for moving the crane. 512

Other objects and advantages will appear in the following specification, and the novel features of my invention will be particularly pointed out in what I hereinafter claim.

My invention is illustrated in the accompanying drawing forming a part of this ap plication, in which:

Figure 1 is a top plan view of the device shown operatively applied to a truck of standard construction;

gigure 2 is a side elevation of the device; an

Figure 3 is a section along the line 3-8 of Figure 2.

In carrying out my invention I make use In this of a truck chassis 1 that is supported by w the truck chasis, preferably at the rear end of.

the truck. The crane comprises a bull wheel 8, a stiff leg 9 and a boom 10, The stiff leg is supported at its upper end by sleeve 11 and sleeve 12, and these in turn are held in place by reinforcing rods 13 and 14. The

boom is raised and lowered and is rotated 7 into the two dotted line positions shown in Figure 1 by a mechanism hereinafter described. I

In addition to the hoisting crane I provide a movable weight 15 that is connected with the crane so that it will be disposed approximately diametrically opposite from the boom, regardless of the particular position of the latter. In the present drawing I have shown the weight as being movable on tracks 16 that extend transversely across the truck chassis. These tracks could be slightly curved without departing from the-spirit and scope of my invention. When the boom 10 is moved into the position A, the weight 15 will be moved toward the bottom of the drawing shown in Figure 1 and will be moved into the opposite position when the boom isswung into the position B. The

positions A and B are substantially the .ex-

treme positions of travel and I have found this is sufficient for all practical purposes.

The means for simultaneously swinging the boom and .for moving the weight comprises a shaft 17 that has two sets of drums 18 and 19 mounted thereon. A cable 20 leads from the drums 18 and is passed around the bull wheel 8. A rotation of the shaft will rotate the bull wheel. Cables 21 are wrapped around the drums 19 and have their free ends passed over pulleys 22 and secured to the ends of the weight 15, as at 28. The cables 20 and 21 are so arranged that they will swing the boom 10 and move the weight 15 so that the weight will be disposed approximately diametrically oposite the boom at all times. This, of course, is not abso lutely true, but the slight variation is compensated for by the fact that the weight moves further away from the rotating center of the hoisting crane as the boom is moved nearer the positions A or B.

A drum 24 is mounted adjacent to the drums l8 and 19 and has a cable 25 feeding therefrom that connects with a boom, and the stiff leg, for raising and lowering the boom. The cable 25 is passed around pulleys 26, 27, and 28, and is secured to a link 29.

The means for raising and lowering the load comprises a drum and a cable 31.

This cable is passed over a pulley 32, a pulley 33 at the end of the boom, and has its end connected to a hook 34.

The drums l8, 19, 24, and 30 are driven from a common counter-shaft 35 and this in turn is connected to a shaft 36 of an auxiliary transmission 37. The transmission 37 is connected by means of a shaft 38 to the main transmission 6. The auxiliary transmission has-three forward speeds and one reverse in the same manner as the main transmission, and the speeds are controlled by a lever 39.

All of the drums carry worm gears that, in turn are operated by worms. The worms are mounted upon shafts and these shafts are operatively connected to the counter shaft 35 by sprocket and chains 40, and clutches 41.

From the foregoing description of the various parts of the device, the operation thereof may readily be understood.

The truck is manipulated in the usual manner. l Vhen the driver wishes to actuate the crane, he can move the lever 39 so to start the counter-shaft 35 rotating. The shaft 38 rotates so long as the engine is running. This is peculiar to the type of truck upon which this device is mounted. The shaft 36 is connected to the shaft by a chain and sprockets 42.

If the boom is desired to be raised or lowered, one of the levers 43 is manipulated for connecting the necessary clutch with the drum 24. The transmission 37 may be thrown into forward or reverse for either raising or lowering the boom.

If the boom is desired to be rotated, the necessary lever 43 and clutch 41 are moved for transmitting motion from the countershaft 35 to the shaft 17. This rotates the bull wheel 8 and moves the weight 15, as already described. The hook 34 is raised and lowered by the drum 30 and this drum may be connected with the source of power by its clutch 41 and lever 43.

The principal point of the invention is the moving of the weight 15 so as to counterbalance the load carried by the hook 34. This permits'the device to be supported by a standard truck without there being any chance of overturning the truck.

Although I have shown and described one embodiment of my invention, it is to be understood that the same is susceptible of various changes and I reserve the right to employ such changes as may come within the scope of the invention as claimed.

1 claim:

1. A truck hoisting crane comprising a chassis, a crane carried by said chassis, means for rotatin said crane, and a weight supported by said chassis independently of said crane, said crane moving means being connected to said weight for moving said weight into a position to counter-balance said crane.

2. A truck hoistin crane comprising a chassis, a crane mounted on said chassis, and having a boom pivoted to a fixed bull wheel, a weight movable transversely across the chassis and common means for moving said crane and weight into positions for causing the weight to counter-balance the crane.

3. in a device of the type described, a common shaft having two sets of drums mounted tl'iereon, a crane, a weight, a cable operatively connected to said crane, and having its ends connected to one set of drums, a pair of cables connected to the second set of drums, and having their ends connected to said weight whereby a, rotation of said shaft will simultaneously rotate the crane and move the weight.

4. A derrick truck comprising a movable frame, a boom having a universal connection to said frame, means for rotating the boom, and a weight movably carried by said frame and being connected to said means for co liter-balancing the boom.

5. A derrick truck comprising a frame, a crane rotatably carried by said frame and having a boom and a lifting h'ook, a weight carried by said frame and being movable transversely thereto, common means for rotating said crane and for moving the weight to counter-balance the crane, and I means carried by said frame for raising and lowering said boom and hook. V

ELMER C. PTTCHER; 

